Overview
ISO 24627-3:2021 - part of the Comprehensive Annotation Framework (ComAF) - defines Diagrammatic Semantic Authoring (DSA): a metamodel for representing documents (instance data) as graphs. DSA specifies how to model documents as labelled directed graphs composed of referenceable parts called segments (graph segments and data segments). It is focused on representation (the document schema), not on visualization, user interaction, or annotations to existing documents.
Key topics and technical requirements
- Segments: Every markable part of a DSA document is a segment; the document itself is a segment.
- Graph segments: Labelled directed graphs made of nodes and links.
- Data segments: Non-graph content (text, image, audio, video) that can embed smaller data segments.
- Nodes and links: A node is a segment; a link is a relation between two end‑nodes (source and destination). Graphs are directed and labelled.
- Hypernodes and embedding: A node can itself be another graph segment (a hypernode), enabling hierarchical composition of arbitrarily large documents from smaller graph segments.
- Multimodality and syntactic annotation: Data segments may be accompanied by syntactic annotations and can represent temporal order and dependency/constituent relations (illustrated in informative examples).
- Scope limitations: DSA specifies the document metamodel only - it does not mandate visualization, editing operations, or mappings to formal semantics; Annex A provides informative visualization examples only.
- Interoperability note: DSA is described as a minimal metamodel for other semantic frameworks (e.g., SemAF-DS) and is intended to enable conversions between DSA-based documents and machine‑understandable semantic representations.
Applications and users
Who benefits from ISO 24627-3:2021:
- NLP engineers and computational linguists building annotation tools and structured authoring systems.
- Tool and UI designers creating graph-based editors for semantic authoring (concept maps, argument maps, diagrammatic editors).
- Knowledge engineers and ontology/terminology teams needing a standardized way to represent document instances as graphs.
- Digital humanities, legal, medical, and patent authors who can exploit explicit logical structures to improve composition, collaboration, and automated conversion to machine-readable formats.
Practical uses include structured authoring, collaborative semantic editing, and intermediate representations enabling automated generation of traditional text or semantic metadata.
Related standards
Keywords: ISO 24627-3:2021, DSA, Diagrammatic semantic authoring, ComAF, language resource management, graph-based representation, hypernode, segment, semantic authoring.
